Files
OCR/backend/app/services/table_content_rebuilder.py
egg 940a406dce chore: backup before code cleanup
Backup commit before executing remove-unused-code proposal.
This includes all pending changes and new features.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
2025-12-11 11:55:39 +08:00

807 lines
28 KiB
Python

"""
Table Content Rebuilder
Rebuilds table content from raw OCR regions when PP-StructureV3's HTML output
is incorrect due to cell merge errors or boundary detection issues.
This module addresses the key problem: PP-StructureV3's ML-based table recognition
often merges multiple cells incorrectly, especially for borderless tables.
The solution uses:
1. cell_boxes validation (filter out-of-bounds cells)
2. Raw OCR regions to rebuild accurate cell content
3. Grid-based row/col position calculation
"""
import logging
from dataclasses import dataclass
from typing import List, Dict, Any, Optional, Tuple
from collections import defaultdict
logger = logging.getLogger(__name__)
@dataclass
class CellBox:
"""Represents a validated cell bounding box."""
x0: float
y0: float
x1: float
y1: float
original_index: int
@property
def center_y(self) -> float:
return (self.y0 + self.y1) / 2
@property
def center_x(self) -> float:
return (self.x0 + self.x1) / 2
@property
def area(self) -> float:
return max(0, (self.x1 - self.x0) * (self.y1 - self.y0))
@dataclass
class OCRTextRegion:
"""Represents a raw OCR text region."""
text: str
x0: float
y0: float
x1: float
y1: float
confidence: float = 1.0
@property
def center_y(self) -> float:
return (self.y0 + self.y1) / 2
@property
def center_x(self) -> float:
return (self.x0 + self.x1) / 2
@dataclass
class RebuiltCell:
"""Represents a rebuilt table cell."""
row: int
col: int
row_span: int
col_span: int
content: str
bbox: Optional[List[float]] = None
ocr_regions: List[OCRTextRegion] = None
def __post_init__(self):
if self.ocr_regions is None:
self.ocr_regions = []
class TableContentRebuilder:
"""
Rebuilds table content from raw OCR regions and validated cell_boxes.
This class solves the problem where PP-StructureV3's HTML output incorrectly
merges multiple cells. Instead of relying on the ML-generated HTML, it:
1. Validates cell_boxes against table bbox
2. Groups cell_boxes into rows/columns by coordinate clustering
3. Fills each cell with matching raw OCR text
4. Generates correct table structure
"""
def __init__(
self,
boundary_tolerance: float = 20.0,
row_clustering_threshold: float = 15.0,
col_clustering_threshold: float = 15.0,
iou_threshold_for_ocr_match: float = 0.3,
min_text_coverage: float = 0.5
):
"""
Initialize the rebuilder.
Args:
boundary_tolerance: Tolerance for cell_boxes boundary check (pixels)
row_clustering_threshold: Max Y-distance for cells in same row (pixels)
col_clustering_threshold: Max X-distance for cells in same column (pixels)
iou_threshold_for_ocr_match: Min IoU to consider OCR region inside cell
min_text_coverage: Min overlap ratio for OCR text to be assigned to cell
"""
self.boundary_tolerance = boundary_tolerance
self.row_clustering_threshold = row_clustering_threshold
self.col_clustering_threshold = col_clustering_threshold
self.iou_threshold = iou_threshold_for_ocr_match
self.min_text_coverage = min_text_coverage
def validate_cell_boxes(
self,
cell_boxes: List[List[float]],
table_bbox: List[float]
) -> Tuple[List[CellBox], Dict[str, Any]]:
"""
Validate cell_boxes against table bbox, filtering invalid ones.
Args:
cell_boxes: List of cell bounding boxes [[x0, y0, x1, y1], ...]
table_bbox: Table bounding box [x0, y0, x1, y1]
Returns:
Tuple of (valid_cells, validation_stats)
"""
if not cell_boxes or len(table_bbox) < 4:
return [], {"total": 0, "valid": 0, "invalid": 0, "reason": "empty_input"}
table_x0, table_y0, table_x1, table_y1 = table_bbox[:4]
table_height = table_y1 - table_y0
table_width = table_x1 - table_x0
# Expanded table bounds with tolerance
expanded_y1 = table_y1 + self.boundary_tolerance
expanded_x1 = table_x1 + self.boundary_tolerance
expanded_y0 = table_y0 - self.boundary_tolerance
expanded_x0 = table_x0 - self.boundary_tolerance
valid_cells = []
invalid_reasons = defaultdict(int)
for idx, box in enumerate(cell_boxes):
if not box or len(box) < 4:
invalid_reasons["invalid_format"] += 1
continue
x0, y0, x1, y1 = box[:4]
# Check if cell is significantly outside table bounds
# Cell's bottom (y1) shouldn't exceed table's bottom + tolerance
if y1 > expanded_y1:
invalid_reasons["y1_exceeds_table"] += 1
continue
# Cell's top (y0) shouldn't be above table's top - tolerance
if y0 < expanded_y0:
invalid_reasons["y0_above_table"] += 1
continue
# Cell's right (x1) shouldn't exceed table's right + tolerance
if x1 > expanded_x1:
invalid_reasons["x1_exceeds_table"] += 1
continue
# Cell's left (x0) shouldn't be left of table - tolerance
if x0 < expanded_x0:
invalid_reasons["x0_left_of_table"] += 1
continue
# Check for inverted coordinates
if x0 >= x1 or y0 >= y1:
invalid_reasons["inverted_coords"] += 1
continue
# Check cell height is reasonable (at least 8px for readable text)
cell_height = y1 - y0
if cell_height < 8:
invalid_reasons["too_small"] += 1
continue
valid_cells.append(CellBox(
x0=x0, y0=y0, x1=x1, y1=y1,
original_index=idx
))
stats = {
"total": len(cell_boxes),
"valid": len(valid_cells),
"invalid": len(cell_boxes) - len(valid_cells),
"invalid_reasons": dict(invalid_reasons),
"validity_ratio": len(valid_cells) / len(cell_boxes) if cell_boxes else 0
}
logger.info(
f"Cell box validation: {stats['valid']}/{stats['total']} valid "
f"(ratio={stats['validity_ratio']:.2%})"
)
if invalid_reasons:
logger.debug(f"Invalid reasons: {dict(invalid_reasons)}")
return valid_cells, stats
def parse_raw_ocr_regions(
self,
raw_regions: List[Dict[str, Any]],
table_bbox: List[float]
) -> List[OCRTextRegion]:
"""
Parse raw OCR regions and filter to those within/near table bbox.
Args:
raw_regions: List of raw OCR region dicts with 'text', 'bbox', 'confidence'
table_bbox: Table bounding box [x0, y0, x1, y1]
Returns:
List of OCRTextRegion objects within table area
"""
if not raw_regions or len(table_bbox) < 4:
return []
table_x0, table_y0, table_x1, table_y1 = table_bbox[:4]
# Expand table area slightly to catch edge text
margin = 10
result = []
for region in raw_regions:
text = region.get('text', '').strip()
if not text:
continue
bbox = region.get('bbox', [])
confidence = region.get('confidence', 1.0)
# Parse bbox (handle both nested and flat formats)
if not bbox:
continue
if isinstance(bbox[0], (list, tuple)):
# Nested format: [[x1,y1], [x2,y2], [x3,y3], [x4,y4]]
xs = [pt[0] for pt in bbox if len(pt) >= 2]
ys = [pt[1] for pt in bbox if len(pt) >= 2]
if xs and ys:
x0, y0, x1, y1 = min(xs), min(ys), max(xs), max(ys)
else:
continue
elif len(bbox) == 4:
x0, y0, x1, y1 = bbox
else:
continue
# Check if region overlaps with table area
if (x1 < table_x0 - margin or x0 > table_x1 + margin or
y1 < table_y0 - margin or y0 > table_y1 + margin):
continue
result.append(OCRTextRegion(
text=text,
x0=float(x0), y0=float(y0),
x1=float(x1), y1=float(y1),
confidence=confidence
))
logger.debug(f"Parsed {len(result)} OCR regions within table area")
return result
def cluster_cells_into_grid(
self,
cells: List[CellBox]
) -> Tuple[List[float], List[float], Dict[Tuple[int, int], CellBox]]:
"""
Cluster cells into rows and columns based on coordinates.
Args:
cells: List of validated CellBox objects
Returns:
Tuple of (row_boundaries, col_boundaries, cell_grid)
- row_boundaries: Y coordinates for row divisions
- col_boundaries: X coordinates for column divisions
- cell_grid: Dict mapping (row, col) to CellBox
"""
if not cells:
return [], [], {}
# Collect all unique Y boundaries (top and bottom of cells)
y_coords = set()
x_coords = set()
for cell in cells:
y_coords.add(round(cell.y0, 1))
y_coords.add(round(cell.y1, 1))
x_coords.add(round(cell.x0, 1))
x_coords.add(round(cell.x1, 1))
# Cluster nearby coordinates
row_boundaries = self._cluster_coordinates(sorted(y_coords), self.row_clustering_threshold)
col_boundaries = self._cluster_coordinates(sorted(x_coords), self.col_clustering_threshold)
logger.debug(f"Found {len(row_boundaries)} row boundaries, {len(col_boundaries)} col boundaries")
# Map cells to grid positions
cell_grid = {}
for cell in cells:
# Find row (based on cell's top Y coordinate)
row = self._find_position(cell.y0, row_boundaries)
# Find column (based on cell's left X coordinate)
col = self._find_position(cell.x0, col_boundaries)
if row is not None and col is not None:
# Check for span (if cell extends across multiple rows/cols)
row_end = self._find_position(cell.y1, row_boundaries)
col_end = self._find_position(cell.x1, col_boundaries)
# Store with potential span info
if (row, col) not in cell_grid:
cell_grid[(row, col)] = cell
return row_boundaries, col_boundaries, cell_grid
def _cluster_coordinates(
self,
coords: List[float],
threshold: float
) -> List[float]:
"""Cluster nearby coordinates into distinct values."""
if not coords:
return []
clustered = [coords[0]]
for coord in coords[1:]:
if coord - clustered[-1] > threshold:
clustered.append(coord)
return clustered
def _find_position(
self,
value: float,
boundaries: List[float]
) -> Optional[int]:
"""Find which position (index) a value falls into."""
for i, boundary in enumerate(boundaries):
if value <= boundary + self.row_clustering_threshold:
return i
return len(boundaries) - 1 if boundaries else None
def assign_ocr_to_cells(
self,
cells: List[CellBox],
ocr_regions: List[OCRTextRegion],
row_boundaries: List[float],
col_boundaries: List[float]
) -> Dict[Tuple[int, int], List[OCRTextRegion]]:
"""
Assign OCR text regions to cells based on spatial overlap.
Args:
cells: List of validated CellBox objects
ocr_regions: List of OCRTextRegion objects
row_boundaries: Y coordinates for row divisions
col_boundaries: X coordinates for column divisions
Returns:
Dict mapping (row, col) to list of OCR regions in that cell
"""
cell_ocr_map: Dict[Tuple[int, int], List[OCRTextRegion]] = defaultdict(list)
for ocr in ocr_regions:
best_cell = None
best_overlap = 0
for cell in cells:
overlap = self._calculate_overlap_ratio(
(ocr.x0, ocr.y0, ocr.x1, ocr.y1),
(cell.x0, cell.y0, cell.x1, cell.y1)
)
if overlap > best_overlap and overlap >= self.min_text_coverage:
best_overlap = overlap
best_cell = cell
if best_cell:
row = self._find_position(best_cell.y0, row_boundaries)
col = self._find_position(best_cell.x0, col_boundaries)
if row is not None and col is not None:
cell_ocr_map[(row, col)].append(ocr)
return cell_ocr_map
def _calculate_overlap_ratio(
self,
box1: Tuple[float, float, float, float],
box2: Tuple[float, float, float, float]
) -> float:
"""Calculate overlap ratio of box1 with box2."""
x0_1, y0_1, x1_1, y1_1 = box1
x0_2, y0_2, x1_2, y1_2 = box2
# Calculate intersection
inter_x0 = max(x0_1, x0_2)
inter_y0 = max(y0_1, y0_2)
inter_x1 = min(x1_1, x1_2)
inter_y1 = min(y1_1, y1_2)
if inter_x0 >= inter_x1 or inter_y0 >= inter_y1:
return 0.0
inter_area = (inter_x1 - inter_x0) * (inter_y1 - inter_y0)
box1_area = (x1_1 - x0_1) * (y1_1 - y0_1)
return inter_area / box1_area if box1_area > 0 else 0.0
def rebuild_table(
self,
cell_boxes: List[List[float]],
table_bbox: List[float],
raw_ocr_regions: List[Dict[str, Any]],
original_html: str = ""
) -> Tuple[Dict[str, Any], Dict[str, Any]]:
"""
Rebuild table content from cell_boxes and raw OCR regions.
This is the main entry point. It:
1. Validates cell_boxes
2. If validity ratio is low, uses pure OCR-based rebuild
3. Otherwise, uses cell_boxes + OCR hybrid rebuild
Args:
cell_boxes: List of cell bounding boxes from PP-StructureV3
table_bbox: Table bounding box [x0, y0, x1, y1]
raw_ocr_regions: List of raw OCR region dicts
original_html: Original HTML from PP-StructureV3 (for fallback)
Returns:
Tuple of (rebuilt_table_dict, rebuild_stats)
"""
stats = {
"action": "none",
"reason": "",
"original_cell_count": len(cell_boxes) if cell_boxes else 0,
"valid_cell_count": 0,
"ocr_regions_in_table": 0,
"rebuilt_rows": 0,
"rebuilt_cols": 0
}
# Step 1: Validate cell_boxes
valid_cells, validation_stats = self.validate_cell_boxes(cell_boxes, table_bbox)
stats["valid_cell_count"] = validation_stats["valid"]
stats["validation"] = validation_stats
# Step 2: Parse raw OCR regions in table area
ocr_regions = self.parse_raw_ocr_regions(raw_ocr_regions, table_bbox)
stats["ocr_regions_in_table"] = len(ocr_regions)
if not ocr_regions:
stats["action"] = "skip"
stats["reason"] = "no_ocr_regions_in_table"
return None, stats
# Step 3: Choose rebuild strategy based on cell_boxes validity
# If validity ratio is too low (< 50%), use pure OCR-based rebuild
if validation_stats["validity_ratio"] < 0.5 or len(valid_cells) < 2:
logger.info(
f"Using pure OCR-based rebuild (validity={validation_stats['validity_ratio']:.2%})"
)
return self._rebuild_from_ocr_only(ocr_regions, table_bbox, stats)
# Otherwise, use hybrid cell_boxes + OCR rebuild
return self._rebuild_with_cell_boxes(valid_cells, ocr_regions, stats, table_bbox)
def _rebuild_from_ocr_only(
self,
ocr_regions: List[OCRTextRegion],
table_bbox: List[float],
stats: Dict[str, Any]
) -> Tuple[Dict[str, Any], Dict[str, Any]]:
"""
Rebuild table using only OCR regions (when cell_boxes are unreliable).
Strategy:
1. Detect column boundary from OCR x-coordinates
2. Cluster OCR regions by Y coordinate into rows
3. Split each row into left/right columns
"""
if not ocr_regions:
stats["action"] = "skip"
stats["reason"] = "no_ocr_regions"
return None, stats
# Get table bounds
table_x0, table_y0, table_x1, table_y1 = table_bbox[:4]
table_width = table_x1 - table_x0
# Step 1: Detect column split point by analyzing x-coordinates
# Look for the gap between left column (x0 < 250) and right column (x0 >= 250)
col_split_x = self._detect_column_split(ocr_regions, table_bbox)
logger.debug(f"Detected column split at x={col_split_x}")
# Step 2: Cluster OCR regions by Y coordinate into rows
# Use smaller threshold (12px) to properly separate rows
row_threshold = 12.0
sorted_ocr = sorted(ocr_regions, key=lambda r: r.center_y)
rows = []
current_row = [sorted_ocr[0]]
for ocr in sorted_ocr[1:]:
if ocr.center_y - current_row[-1].center_y <= row_threshold:
current_row.append(ocr)
else:
rows.append(current_row)
current_row = [ocr]
rows.append(current_row)
logger.debug(f"Detected {len(rows)} rows")
# Step 3: Analyze column structure
left_regions = [r for r in ocr_regions if r.x0 < col_split_x]
right_regions = [r for r in ocr_regions if r.x0 >= col_split_x]
num_cols = 2 if len(left_regions) >= 2 and len(right_regions) >= 2 else 1
# Step 4: Build cells for each row
rebuilt_cells = []
for row_idx, row_ocrs in enumerate(rows):
row_ocrs_sorted = sorted(row_ocrs, key=lambda r: r.center_x)
if num_cols == 2:
# Split into left and right columns using x0
left_ocrs = [r for r in row_ocrs_sorted if r.x0 < col_split_x]
right_ocrs = [r for r in row_ocrs_sorted if r.x0 >= col_split_x]
# Left column cell
if left_ocrs:
left_content = " ".join(r.text for r in left_ocrs)
left_bbox = [
min(r.x0 for r in left_ocrs),
min(r.y0 for r in left_ocrs),
max(r.x1 for r in left_ocrs),
max(r.y1 for r in left_ocrs)
]
rebuilt_cells.append({
"row": row_idx,
"col": 0,
"row_span": 1,
"col_span": 1,
"content": left_content,
"bbox": left_bbox
})
# Right column cell
if right_ocrs:
right_content = " ".join(r.text for r in right_ocrs)
right_bbox = [
min(r.x0 for r in right_ocrs),
min(r.y0 for r in right_ocrs),
max(r.x1 for r in right_ocrs),
max(r.y1 for r in right_ocrs)
]
rebuilt_cells.append({
"row": row_idx,
"col": 1,
"row_span": 1,
"col_span": 1,
"content": right_content,
"bbox": right_bbox
})
else:
# Single column - merge all OCR in row
row_content = " ".join(r.text for r in row_ocrs_sorted)
row_bbox = [
min(r.x0 for r in row_ocrs_sorted),
min(r.y0 for r in row_ocrs_sorted),
max(r.x1 for r in row_ocrs_sorted),
max(r.y1 for r in row_ocrs_sorted)
]
rebuilt_cells.append({
"row": row_idx,
"col": 0,
"row_span": 1,
"col_span": 1,
"content": row_content,
"bbox": row_bbox
})
num_rows = len(rows)
stats["rebuilt_rows"] = num_rows
stats["rebuilt_cols"] = num_cols
# Build result
rebuilt_table = {
"rows": num_rows,
"cols": num_cols,
"cells": rebuilt_cells,
"html": self._generate_html(rebuilt_cells, num_rows, num_cols),
"rebuild_source": "pure_ocr"
}
stats["action"] = "rebuilt"
stats["reason"] = "pure_ocr_success"
stats["rebuilt_cell_count"] = len(rebuilt_cells)
logger.info(
f"Table rebuilt (pure OCR): {num_rows}x{num_cols} with {len(rebuilt_cells)} cells"
)
return rebuilt_table, stats
def _detect_column_split(
self,
ocr_regions: List[OCRTextRegion],
table_bbox: List[float]
) -> float:
"""
Detect the column split point by analyzing x-coordinates.
For tables with left/right structure (e.g., property-value tables),
there's usually a gap between left column text and right column text.
"""
if not ocr_regions:
return (table_bbox[0] + table_bbox[2]) / 2
# Collect all x0 values (left edge of each text region)
x0_values = sorted(set(round(r.x0) for r in ocr_regions))
if len(x0_values) < 2:
return (table_bbox[0] + table_bbox[2]) / 2
# Find the largest gap between consecutive x0 values
# This usually indicates the column boundary
max_gap = 0
split_point = (table_bbox[0] + table_bbox[2]) / 2
for i in range(len(x0_values) - 1):
gap = x0_values[i + 1] - x0_values[i]
if gap > max_gap and gap > 50: # Require minimum 50px gap
max_gap = gap
split_point = (x0_values[i] + x0_values[i + 1]) / 2
# If no clear gap found, use table center
if max_gap < 50:
split_point = (table_bbox[0] + table_bbox[2]) / 2
return split_point
def _rebuild_with_cell_boxes(
self,
valid_cells: List[CellBox],
ocr_regions: List[OCRTextRegion],
stats: Dict[str, Any],
table_bbox: Optional[List[float]] = None
) -> Tuple[Dict[str, Any], Dict[str, Any]]:
"""Rebuild table using cell_boxes structure + OCR content."""
# Step 3: Cluster cells into grid
row_boundaries, col_boundaries, cell_grid = self.cluster_cells_into_grid(valid_cells)
num_rows = len(row_boundaries) - 1 if len(row_boundaries) > 1 else 1
num_cols = len(col_boundaries) - 1 if len(col_boundaries) > 1 else 1
# Quality check: if hybrid produces too many columns or sparse grid, fall back to pure OCR
# A well-formed table typically has 2-5 columns. Too many columns indicates poor clustering.
total_expected_cells = num_rows * num_cols
if num_cols > 5 or total_expected_cells > 100:
logger.info(
f"Hybrid mode produced {num_rows}x{num_cols} grid (too sparse), "
f"falling back to pure OCR mode"
)
if table_bbox:
return self._rebuild_from_ocr_only(ocr_regions, table_bbox, stats)
stats["rebuilt_rows"] = num_rows
stats["rebuilt_cols"] = num_cols
# Step 4: Assign OCR text to cells
cell_ocr_map = self.assign_ocr_to_cells(
valid_cells, ocr_regions, row_boundaries, col_boundaries
)
# Step 5: Build rebuilt cells
rebuilt_cells = []
for (row, col), ocr_list in cell_ocr_map.items():
# Sort OCR regions by position (top to bottom, left to right)
sorted_ocr = sorted(ocr_list, key=lambda r: (r.center_y, r.center_x))
content = " ".join(r.text for r in sorted_ocr)
# Find the cell bbox for this position
cell_bbox = None
for cell in valid_cells:
cell_row = self._find_position(cell.y0, row_boundaries)
cell_col = self._find_position(cell.x0, col_boundaries)
if cell_row == row and cell_col == col:
cell_bbox = [cell.x0, cell.y0, cell.x1, cell.y1]
break
rebuilt_cells.append({
"row": row,
"col": col,
"row_span": 1,
"col_span": 1,
"content": content,
"bbox": cell_bbox
})
# Quality check: if too few cells have content compared to grid size, fall back to pure OCR
content_ratio = len(rebuilt_cells) / total_expected_cells if total_expected_cells > 0 else 0
if content_ratio < 0.3 and table_bbox:
logger.info(
f"Hybrid mode has low content ratio ({content_ratio:.2%}), "
f"falling back to pure OCR mode"
)
return self._rebuild_from_ocr_only(ocr_regions, table_bbox, stats)
# Build result
rebuilt_table = {
"rows": num_rows,
"cols": num_cols,
"cells": rebuilt_cells,
"html": self._generate_html(rebuilt_cells, num_rows, num_cols),
"rebuild_source": "cell_boxes_hybrid"
}
stats["action"] = "rebuilt"
stats["reason"] = "hybrid_success"
stats["rebuilt_cell_count"] = len(rebuilt_cells)
logger.info(
f"Table rebuilt (hybrid): {num_rows}x{num_cols} with {len(rebuilt_cells)} cells "
f"(from {len(ocr_regions)} OCR regions)"
)
return rebuilt_table, stats
def _generate_html(
self,
cells: List[Dict[str, Any]],
num_rows: int,
num_cols: int
) -> str:
"""Generate HTML table from rebuilt cells."""
# Create grid
grid = [[None for _ in range(num_cols)] for _ in range(num_rows)]
for cell in cells:
row, col = cell["row"], cell["col"]
if 0 <= row < num_rows and 0 <= col < num_cols:
grid[row][col] = cell["content"]
# Build HTML
html_parts = ["<html><body><table>"]
for row_idx in range(num_rows):
html_parts.append("<tr>")
for col_idx in range(num_cols):
content = grid[row_idx][col_idx] or ""
tag = "th" if row_idx == 0 else "td"
html_parts.append(f"<{tag}>{content}</{tag}>")
html_parts.append("</tr>")
html_parts.append("</table></body></html>")
return "".join(html_parts)
def should_rebuild(
self,
cell_boxes: List[List[float]],
table_bbox: List[float],
original_html: str = ""
) -> Tuple[bool, str]:
"""
Determine if table should be rebuilt based on cell_boxes validity.
Args:
cell_boxes: List of cell bounding boxes
table_bbox: Table bounding box
original_html: Original HTML from PP-StructureV3
Returns:
Tuple of (should_rebuild, reason)
"""
if not cell_boxes:
return False, "no_cell_boxes"
_, validation_stats = self.validate_cell_boxes(cell_boxes, table_bbox)
# Always rebuild if ANY cells are invalid - PP-Structure HTML often merges cells incorrectly
# even when most cell_boxes are valid
if validation_stats["invalid"] > 0:
return True, f"invalid_cells_{validation_stats['invalid']}/{validation_stats['total']}"
# Rebuild if there are boundary violations
invalid_reasons = validation_stats.get("invalid_reasons", {})
boundary_violations = (
invalid_reasons.get("y1_exceeds_table", 0) +
invalid_reasons.get("y0_above_table", 0) +
invalid_reasons.get("x1_exceeds_table", 0) +
invalid_reasons.get("x0_left_of_table", 0)
)
if boundary_violations > 0:
return True, f"boundary_violations_{boundary_violations}"
# Also rebuild to ensure OCR-based content is used instead of PP-Structure HTML
# PP-Structure's HTML often has incorrect cell merging
return True, "ocr_content_preferred"